Objective The aim of this study is to investigate whether microwave exposure would affect the N-methyI-D-aspartate receptor （NMDAR） signaling pathway to establish whether this plays a role in synaptic plasticity imp...Objective The aim of this study is to investigate whether microwave exposure would affect the N-methyI-D-aspartate receptor （NMDAR） signaling pathway to establish whether this plays a role in synaptic plasticity impairment. Methods 48 male Wistar rats were exposed to 30 mW/cm^2 microwave for 10 min every other day for three times. Hippocampal structure was observed through H＆E staining and transmission electron microscope. PC12 cells were exposed to 30 mW/cm^2 microwave for 5 min and the synapse morphology was visualized with scanning electron microscope and atomic force microscope. The release of amino acid neurotransmitters and calcium influx were detected. The expressions of several key NMDAR signaling molecules were evaluated. Results Microwave exposure caused injury in rat hippocampal structure and PC12 cells, especially the structure and quantity of synapses. The ratio of glutamic acid and gamma-aminobutyric acid neurotransmitters was increased and the intracellular calcium level was elevated in PC12 cells. A significant change in NMDAR subunits （NR1, NR2A, and NR2B） and related signaling molecules （CaZ＋/calmodulin-dependent kinase II gamma and phosphorylated cAMP-response element binding protein） were examined. Conclusion 30 mW/cm^2 microwave exposure resulted in alterations of synaptic structure, amino acid neurotransmitter release and calcium influx. NMDAR signaling molecules were closely associated with impaired synaptic plasticity.展开更多
Objective： To observe the effects of electroacupuncture （EA） on the structure parameters of synapse and reactive changes of astrocyte in the marginal zone of focal cerebral ischemia in rats at different time zones ...Objective： To observe the effects of electroacupuncture （EA） on the structure parameters of synapse and reactive changes of astrocyte in the marginal zone of focal cerebral ischemia in rats at different time zones so as to further explore its underlying mechanisms in the treatment of cerebral ischemia. Methods： Ninety male Wistar rats were randomly assigned to sham-operation, model, and EA groups, with 30 animals in each group. Each group was subdivided into 1 h, as well as 1, 3, 7, and 21 days post-operation groups, with 6 animals assigned to each time point subgroup. Heat coagulation-induced occlusion of the middle cerebral artery was performed to establish a model of focal cerebral ischemia. EA was applied immediately following surgery to the EA group [4/20 Hz, 2.0-3.0 V, 1-3 mA, to Baihui （GV20） and Dazhui （GV14）] for 30 min. Treatment was performed once a day, and experimental animals were sacrificed at 1 h, as well as 1, 3, 7 and 21 days postoperation. The ultrastructure changes in synapse and astrocytes were observed by using transmission electron microscopy. Glial fibrillary acidic protein （GFAP） expression and Ca2＋ of astrocytes were measured by using laser confocal scanning microscope. Excitatory amino acid transporters-2 （EAAT2） and connexin 43 （CX43） expressions were assayed with immunohistochemical method. Canonical correlation analysis was conducted between structure parameters of synapse and parameters of astrocyte in the same time and group. Results： Broken synapses were observed following cerebral ischemia, and the numbers of synapses were significantly decreased. Compared with the model group, synaptic ultrastructure was significantly improved in the EA group. Compared with the sham-operation group, synaptic number density was significantly decreased, as were postsynaptic density thickness, synaptic cleft width and synaptic interface curvature in the EA and model groups. However, compared with the model group, postsynaptic density thickness was significantly increased in the EA group at the same time points post-operation （P〈0.05, P〈0.01）. In addition, synaptic cleft width, synaptic number density and synaptic interface curvature were significantly increased with the passage of time （P〈0.05, P〈0.01）. The expression of GFAP in the EA group were significantly lower than those in the model group at all the time points （P〈0.05, P〈0.01）. OD values of EAAT2 in the EA group were significantly higher than those in the model group at the same time （P〈0.05, P〈0.01）. Compared with that in the model group, the expressions of CX43 in the EA group increased significantly at 3 days and 7 days （P〈0.05, P〈0.01）. Ca2＋ average fluorescence intensity of astrocytes in the EA group was significantly lower than those in the model group at 1 h, 1 day, 3 days and 7 days （P〈0.05, P〈0.01）. The changes in structure parameters of synapse were closely related to the changesof CX43, EAAT2, GFAP, Ca＋ of astrocytes by EA treatment at all the time points. Conclusions： EA is helpful for synaptic reorganization, which may be related to its effect on intervening the activation state of astrocytes and promoting the beneficial interaction between astrocytes and synapses. Acupuncture could start the adjustment of neuron-glial network so as to promote the synaptic reorganization, which may be the key mechanism of treating cerebral ischemia.展开更多
目的探讨朱砂安神丸对条件性恐惧大鼠恐惧记忆的影响及作用机制。方法将90只雄性SD大鼠随机分为空白组、模型组、给药组,每组30只;给药组大鼠灌胃给予朱砂安神丸混悬液(给药体积为每100 g大鼠体质量0.9 m L),空白组、模型组大鼠给予等...目的探讨朱砂安神丸对条件性恐惧大鼠恐惧记忆的影响及作用机制。方法将90只雄性SD大鼠随机分为空白组、模型组、给药组,每组30只;给药组大鼠灌胃给予朱砂安神丸混悬液(给药体积为每100 g大鼠体质量0.9 m L),空白组、模型组大鼠给予等量的双蒸水,各组大鼠均连续干预7 d。末次给药后复制条件性恐惧模型。通过条件性恐惧实验监测系统观察各组大鼠的僵直反应时间,考察朱砂安神丸对恐惧记忆的影响;通过电生理实验和透射电镜技术,考察朱砂安神丸对海马功能结构可塑性的影响。结果与模型组比较,给药组(朱砂安神丸)能有效促进条件性恐惧大鼠恐惧记忆消退,恐惧记忆习得阶段及消退阶段僵直反应时间明显减少,运动时间、运动距离明显增加,诱发海马部位LTP其PS幅值明显减少(P<0.05,P<0.01);海马神经元突触数目较多,突触各部分结构完好、界限清晰,海马突触活性区长度及PSD厚度明显增大,突触间隙宽度明显减小(P<0.05,P<0.01);海马神经元细胞各结构完整清晰,细胞核大,细胞浆内细胞器较多、形态较好。结论朱砂安神丸具有促进恐惧记忆消退的作用,其作用机制与保护海马神经元、调节海马突触结构和功能可塑性有关。展开更多
目的探讨癫痫伴抑郁模型大鼠海马突触相关蛋白突触素(synaptophysin,SYN)、突触后致密蛋白95(postsynaptic density protein 95,PSD95)及生长相关蛋白43(growth-associated protein 43,GAP43)的表达情况。方法选取3月龄雌性清洁级SD大...目的探讨癫痫伴抑郁模型大鼠海马突触相关蛋白突触素(synaptophysin,SYN)、突触后致密蛋白95(postsynaptic density protein 95,PSD95)及生长相关蛋白43(growth-associated protein 43,GAP43)的表达情况。方法选取3月龄雌性清洁级SD大鼠进行实验,采用氯化锂-匹罗卡品建立癫痫大鼠模型,造模成功的癫痫模型大鼠根据是否伴发抑郁分为癫痫伴抑郁组(10只)和癫痫组(10只),另取体质量相匹配的10只大鼠作为抑郁组,10只作为正常组,其中抑郁组大鼠采用慢性不可预见性温和应激刺激结合孤养法建立抑郁模型。采用体质量、糖水偏爱实验和旷场实验评价大鼠的抑郁行为,免疫组织化学染色及Western blot检测大鼠海马组织SYN、PSD95、GAP43蛋白的表达。采用SPSS 17.0软件进行数据统计分析,行为学结果使用重复测量方差分析,蛋白表达数据多组间比较采用单因素方差分析,进一步两两比较采用LSD检验。结果4组大鼠体质量比较,时间和组别的交互作用显著(F=7.33,P<0.01),在第8天和第29天,癫痫伴抑郁组与抑郁组大鼠体质量均低于癫痫组(均P<0.05),癫痫伴抑郁组大鼠体质量在第29天较第1天低(P<0.05);4组大鼠糖水偏爱率比较,时间和组别的交互作用显著(F=2.67,P<0.05),癫痫伴抑郁组大鼠在第15和29天糖水偏爱率较第1天低(均P<0.05);旷场实验结果显示,垂直站立次数(F=2.74)与水平运动格子数(F=1.76)的交互效应作用均不显著(均P>0.05),但时间主效应和组别主效应均显著(垂直站立次数:F时间=4.35,P<0.05,F组间=25.64,P<0.01;水平运动格子数:F时间=12.75,P<0.01,F组间=21.37,P<0.01)。免疫组化结果显示,4组大鼠突触蛋白SYN、PSD95和GAP43阳性表达细胞数比较均差异有统计学意义(F=93.85,58.66,98.84,均P<0.05)。癫痫组SYN[(11.73±4.30)个]、PSD95[(24.47±7.58)个]、GAP43[(9.40±3.50)个]阳性细胞表达数均低于正常组[(51.00±15.39)个、(55.60±13.17)个、(29.53±4.05)个](均P<0.05)。癫痫伴抑郁组SYN[(5.80±3.53)个]、PSD95[(12.87±4.03)个]、GAP43[(5.33±3.50)个]阳性表达细胞数均低于抑郁组[(11.33±3.22)个、(48.13±12.69)个、(15.47±5.21)个](均P<0.05)。Western blot结果显示,4组大鼠突触蛋白SYN、PSD95、GAP43的表达均差异有统计学意义(F=13.19,9.38,16.80,均P<0.05)。癫痫组的SYN、PSD95和GAP43表达水平均低于正常组(均P<0.05)。癫痫伴抑郁组SYN、PSD95和GAP43表达水平均低于癫痫组和抑郁组(均P<0.05)。结论癫痫伴抑郁大鼠海马SYN、PSD95、GAP43蛋白的低表达可能与其发病机制有关。展开更多
水通道蛋白-4(aquaporin-4,AQP-4)作为水通道蛋白家族之一,在中枢神经系统具有广泛的分布,且在星形胶质细胞终足上高表达。研究表明,AQP-4可通过调节星形胶质细胞的功能在维持脑内水稳态、脑体积和神经元兴奋性等方面发挥重要的作用。但...水通道蛋白-4(aquaporin-4,AQP-4)作为水通道蛋白家族之一,在中枢神经系统具有广泛的分布,且在星形胶质细胞终足上高表达。研究表明,AQP-4可通过调节星形胶质细胞的功能在维持脑内水稳态、脑体积和神经元兴奋性等方面发挥重要的作用。但是AQP-4在突触可塑性、学习记忆及认知等方面所发挥的作用还不明了。突触功能可塑性的变化按其性质的不同可分为长时程增强(long term potentiation,LTP)和长时程抑制(long term depression,LTD),两者被公认为是学习记忆的神经生物学基础。海马区是调节学习记忆过程的核心脑区,其突触可塑性与学习记忆有密切的关系。本文旨在综述AQP-4与海马区突触可塑性及相关学习记忆的关系研究进展,并展望AQP-4作为新的靶点在认知功能障碍中的可能作用,为临床治疗相关神经系统疾病提供新的思路与方向。展开更多
基金supported by the National Natural Science Foundation of China(No.81172620)
文摘Objective The aim of this study is to investigate whether microwave exposure would affect the N-methyI-D-aspartate receptor （NMDAR） signaling pathway to establish whether this plays a role in synaptic plasticity impairment. Methods 48 male Wistar rats were exposed to 30 mW/cm^2 microwave for 10 min every other day for three times. Hippocampal structure was observed through H＆E staining and transmission electron microscope. PC12 cells were exposed to 30 mW/cm^2 microwave for 5 min and the synapse morphology was visualized with scanning electron microscope and atomic force microscope. The release of amino acid neurotransmitters and calcium influx were detected. The expressions of several key NMDAR signaling molecules were evaluated. Results Microwave exposure caused injury in rat hippocampal structure and PC12 cells, especially the structure and quantity of synapses. The ratio of glutamic acid and gamma-aminobutyric acid neurotransmitters was increased and the intracellular calcium level was elevated in PC12 cells. A significant change in NMDAR subunits （NR1, NR2A, and NR2B） and related signaling molecules （CaZ＋/calmodulin-dependent kinase II gamma and phosphorylated cAMP-response element binding protein） were examined. Conclusion 30 mW/cm^2 microwave exposure resulted in alterations of synaptic structure, amino acid neurotransmitter release and calcium influx. NMDAR signaling molecules were closely associated with impaired synaptic plasticity.
基金Supported by the National Basic Research Program of China (973 Program,No.2010CB530500)National Natural Science Foundation of China(No.30572420)Program for New Century Excellent Talents in University,Ministry of Education of China (No.NCET-04-0831)
文摘Objective： To observe the effects of electroacupuncture （EA） on the structure parameters of synapse and reactive changes of astrocyte in the marginal zone of focal cerebral ischemia in rats at different time zones so as to further explore its underlying mechanisms in the treatment of cerebral ischemia. Methods： Ninety male Wistar rats were randomly assigned to sham-operation, model, and EA groups, with 30 animals in each group. Each group was subdivided into 1 h, as well as 1, 3, 7, and 21 days post-operation groups, with 6 animals assigned to each time point subgroup. Heat coagulation-induced occlusion of the middle cerebral artery was performed to establish a model of focal cerebral ischemia. EA was applied immediately following surgery to the EA group [4/20 Hz, 2.0-3.0 V, 1-3 mA, to Baihui （GV20） and Dazhui （GV14）] for 30 min. Treatment was performed once a day, and experimental animals were sacrificed at 1 h, as well as 1, 3, 7 and 21 days postoperation. The ultrastructure changes in synapse and astrocytes were observed by using transmission electron microscopy. Glial fibrillary acidic protein （GFAP） expression and Ca2＋ of astrocytes were measured by using laser confocal scanning microscope. Excitatory amino acid transporters-2 （EAAT2） and connexin 43 （CX43） expressions were assayed with immunohistochemical method. Canonical correlation analysis was conducted between structure parameters of synapse and parameters of astrocyte in the same time and group. Results： Broken synapses were observed following cerebral ischemia, and the numbers of synapses were significantly decreased. Compared with the model group, synaptic ultrastructure was significantly improved in the EA group. Compared with the sham-operation group, synaptic number density was significantly decreased, as were postsynaptic density thickness, synaptic cleft width and synaptic interface curvature in the EA and model groups. However, compared with the model group, postsynaptic density thickness was significantly increased in the EA group at the same time points post-operation （P〈0.05, P〈0.01）. In addition, synaptic cleft width, synaptic number density and synaptic interface curvature were significantly increased with the passage of time （P〈0.05, P〈0.01）. The expression of GFAP in the EA group were significantly lower than those in the model group at all the time points （P〈0.05, P〈0.01）. OD values of EAAT2 in the EA group were significantly higher than those in the model group at the same time （P〈0.05, P〈0.01）. Compared with that in the model group, the expressions of CX43 in the EA group increased significantly at 3 days and 7 days （P〈0.05, P〈0.01）. Ca2＋ average fluorescence intensity of astrocytes in the EA group was significantly lower than those in the model group at 1 h, 1 day, 3 days and 7 days （P〈0.05, P〈0.01）. The changes in structure parameters of synapse were closely related to the changesof CX43, EAAT2, GFAP, Ca＋ of astrocytes by EA treatment at all the time points. Conclusions： EA is helpful for synaptic reorganization, which may be related to its effect on intervening the activation state of astrocytes and promoting the beneficial interaction between astrocytes and synapses. Acupuncture could start the adjustment of neuron-glial network so as to promote the synaptic reorganization, which may be the key mechanism of treating cerebral ischemia.
文摘目的探讨朱砂安神丸对条件性恐惧大鼠恐惧记忆的影响及作用机制。方法将90只雄性SD大鼠随机分为空白组、模型组、给药组,每组30只;给药组大鼠灌胃给予朱砂安神丸混悬液(给药体积为每100 g大鼠体质量0.9 m L),空白组、模型组大鼠给予等量的双蒸水,各组大鼠均连续干预7 d。末次给药后复制条件性恐惧模型。通过条件性恐惧实验监测系统观察各组大鼠的僵直反应时间,考察朱砂安神丸对恐惧记忆的影响;通过电生理实验和透射电镜技术,考察朱砂安神丸对海马功能结构可塑性的影响。结果与模型组比较,给药组(朱砂安神丸)能有效促进条件性恐惧大鼠恐惧记忆消退,恐惧记忆习得阶段及消退阶段僵直反应时间明显减少,运动时间、运动距离明显增加,诱发海马部位LTP其PS幅值明显减少(P<0.05,P<0.01);海马神经元突触数目较多,突触各部分结构完好、界限清晰,海马突触活性区长度及PSD厚度明显增大,突触间隙宽度明显减小(P<0.05,P<0.01);海马神经元细胞各结构完整清晰,细胞核大,细胞浆内细胞器较多、形态较好。结论朱砂安神丸具有促进恐惧记忆消退的作用,其作用机制与保护海马神经元、调节海马突触结构和功能可塑性有关。
文摘目的探讨癫痫伴抑郁模型大鼠海马突触相关蛋白突触素(synaptophysin,SYN)、突触后致密蛋白95(postsynaptic density protein 95,PSD95)及生长相关蛋白43(growth-associated protein 43,GAP43)的表达情况。方法选取3月龄雌性清洁级SD大鼠进行实验,采用氯化锂-匹罗卡品建立癫痫大鼠模型,造模成功的癫痫模型大鼠根据是否伴发抑郁分为癫痫伴抑郁组(10只)和癫痫组(10只),另取体质量相匹配的10只大鼠作为抑郁组,10只作为正常组,其中抑郁组大鼠采用慢性不可预见性温和应激刺激结合孤养法建立抑郁模型。采用体质量、糖水偏爱实验和旷场实验评价大鼠的抑郁行为,免疫组织化学染色及Western blot检测大鼠海马组织SYN、PSD95、GAP43蛋白的表达。采用SPSS 17.0软件进行数据统计分析,行为学结果使用重复测量方差分析,蛋白表达数据多组间比较采用单因素方差分析,进一步两两比较采用LSD检验。结果4组大鼠体质量比较,时间和组别的交互作用显著(F=7.33,P<0.01),在第8天和第29天,癫痫伴抑郁组与抑郁组大鼠体质量均低于癫痫组(均P<0.05),癫痫伴抑郁组大鼠体质量在第29天较第1天低(P<0.05);4组大鼠糖水偏爱率比较,时间和组别的交互作用显著(F=2.67,P<0.05),癫痫伴抑郁组大鼠在第15和29天糖水偏爱率较第1天低(均P<0.05);旷场实验结果显示,垂直站立次数(F=2.74)与水平运动格子数(F=1.76)的交互效应作用均不显著(均P>0.05),但时间主效应和组别主效应均显著(垂直站立次数:F时间=4.35,P<0.05,F组间=25.64,P<0.01;水平运动格子数:F时间=12.75,P<0.01,F组间=21.37,P<0.01)。免疫组化结果显示,4组大鼠突触蛋白SYN、PSD95和GAP43阳性表达细胞数比较均差异有统计学意义(F=93.85,58.66,98.84,均P<0.05)。癫痫组SYN[(11.73±4.30)个]、PSD95[(24.47±7.58)个]、GAP43[(9.40±3.50)个]阳性细胞表达数均低于正常组[(51.00±15.39)个、(55.60±13.17)个、(29.53±4.05)个](均P<0.05)。癫痫伴抑郁组SYN[(5.80±3.53)个]、PSD95[(12.87±4.03)个]、GAP43[(5.33±3.50)个]阳性表达细胞数均低于抑郁组[(11.33±3.22)个、(48.13±12.69)个、(15.47±5.21)个](均P<0.05)。Western blot结果显示,4组大鼠突触蛋白SYN、PSD95、GAP43的表达均差异有统计学意义(F=13.19,9.38,16.80,均P<0.05)。癫痫组的SYN、PSD95和GAP43表达水平均低于正常组(均P<0.05)。癫痫伴抑郁组SYN、PSD95和GAP43表达水平均低于癫痫组和抑郁组(均P<0.05)。结论癫痫伴抑郁大鼠海马SYN、PSD95、GAP43蛋白的低表达可能与其发病机制有关。
基金supported by the National Natural Science Foundation of China(No. 81373852)the Key Scientific Research Project of Colleges and Universities in Henan Province+2 种基金China(No. 15A310019)PhD Research Fund of Henan University of Chinese MedicineChina (No. BSJJ-201510)
文摘水通道蛋白-4(aquaporin-4,AQP-4)作为水通道蛋白家族之一,在中枢神经系统具有广泛的分布,且在星形胶质细胞终足上高表达。研究表明,AQP-4可通过调节星形胶质细胞的功能在维持脑内水稳态、脑体积和神经元兴奋性等方面发挥重要的作用。但是AQP-4在突触可塑性、学习记忆及认知等方面所发挥的作用还不明了。突触功能可塑性的变化按其性质的不同可分为长时程增强(long term potentiation,LTP)和长时程抑制(long term depression,LTD),两者被公认为是学习记忆的神经生物学基础。海马区是调节学习记忆过程的核心脑区,其突触可塑性与学习记忆有密切的关系。本文旨在综述AQP-4与海马区突触可塑性及相关学习记忆的关系研究进展,并展望AQP-4作为新的靶点在认知功能障碍中的可能作用,为临床治疗相关神经系统疾病提供新的思路与方向。
